Telephone eeceiveb



May 11 1926.

W. HEUSSER TELEPHONE RECEIV Filed April 14, 1923 m W W m;

ENS EN M Patented May l1, 1926i.

PATENT ortica.

`winnen) niiussnn, oFsALT LAKE CITY, Uren'.

TELEPHONE RECEVER.

ApplicatiOn filed April 14, 1923. Serial No. 632,080.

This invention relatesy to telephone receivers, and other sound reproducing de-` vices, but more especially to thosewhich are applicable to radio telephony.

The principal objects of this invention are to provide aninstrument which shall:

First. Have eXtremey sensitivity.

Second. :Bey rugged andstaunch in construction.

Third. Have few parts, and therefore great simplicity. y v

Fourth. Be `reliable and service Fifth. Be compact in form.

Sixth. Be designed with special regard for quantity production in manufacturing, so that the instruments may be sold at moderate prices. n

This invention is applicable to telephone receivers of various kinds, butfo-r' convenience, its specific application to receivers having tensioned diaphragms, is shown and described herein. 1

In the drawing,l

Fig. 1 represents a section through a. receiver embodying `this invention, taken partly on line 1 and partly on line 1nl in Fig. 4; s y

Fig. 2, section 'on line2, Fig. 4;.

Fig. 3, an elevation in the direction of the arrow 3 in Fig. 4, the casing in the foregroundy being omitted,y and parts shown in section on line 3a; p

Fig. 4, a front elevation partly in section on lline 4, Fig- 2;` y y Fig. 5, an enlargement of the portion en-l durable in closed by the broken line 5, indicate'dvin Fig. 4, co-il omit-ted;

Figs. 6 and 7 sections taken respectively on lines 6 and y7 inFig. 5*; y

Fig. 8, a fragmentary elevation in the direction of arrow 8 in Fig. 7; Fig. 9, a'central cross-section through an instrument having a double actuating mechanism; y

Figs. 10 and 11, enlarged details showing method of suspending one end of the arma.- ture; f

Fig. 12, an enlarged detail showing method of suspending the armature in an instrument having a double actuating mechaf nism; y

Figs. 13 and 14, diagrams of the magnetic circuits in a single instrument; and

Figs. 15 and 16, the same, in a double instrument. n

Referring to the drawing, 20 indicates a permanent magnet having what I choose to call a box or C form,y the po-les 21 and 24 heilig located in the jaws of thev C, direct-ly apart toform an air gap, as shown in Figs- 2 and 3. n

The magnet 20 may be permanent-ly fas tenedpto the foundationplate 25, by any suitable means, for instance, rivets 26. The foundation plate may be countersunk to receive the diaphragm 27. y A second dia phragm 28'may be placed ydirectly opposite the first diaphragm, andk be supported in the holding plate 29. 4The holding plate may be spaced apart from the foundationkplate 25', byy means of the shouldered portions of pins 30, which also have the threaded ends 31 and 32. The ends 31 may be screwed into the foundation'plate while the holding plate may be slippedy over the opposite ends 82,r against the shouldered portions of the pins, as shown in Fig. 3.

Within the magnet .2O maybe the coils 34, made of line wire and wound upon the spool 35 in the usual manner. This spool may have an elongated form as shown in Fig. 1, and havera core space in the form'of the elongated slot at 36. inthe back part of the magnet may be formed the Vshaped groove 37, directly opposite they opening between the poles .21 and 24. The elongated coil 84 may be clamped between the legs of the magnet 2O by the screws 38 (Fig. 1 the latter being intended primarily, however, for adjusting the air gap between the poles or jaws of the permanent magnet. y

- The elongatedl slot should he in central alignment with the gap and with the groove 37. Ar. armature 40, made of suitable inaterial, such as silicon steel or soft iron, and having thehknife edges 41, is placed to rock in the V-shaped groove 37, preferably in the neutral ,part of the magnet 20, as Iclearly shown in-Fig. .6. VBetween the knife edges 41 (Fig. 5)thelarmature40 is provided with countersunk from both sides of the armature plate to formi a circular knife edge.

The knife edges of the armature may be held in the contact with the bottom of the V-groove, by means of a link having the hook portions 45 and46, one hook extending through the eye 43, and the other engaging` a piece of spring wire 47 under tension, which acts in the direction of the arrow 51, (Fig.

opposed to eac-h other, vrand slightly spaced n `a ljug 42, in which may be the eye port-ion 43,

7 The ends of the sp 1ing'4?Y may rest in grooves 48 in the frame of the permanent magnet 20. The lug 42 is accommodated by the hole 49 in the magnet frame, and this hole may be countersunk as shown at 50, to provide clearance for the free movement of the contiguous parts holding the armature. The armature lies in the neutral zone of the magnet, and magnetically contacts the neutral portion of the permanent magnet,

Obviously, the armature 4G, rocking on the knife edges 4l, is free to move to either side'in the directions indicated by the arrows (Fig. 6) with a minimum of friction at its bearing. The other end of the armature 40 is provided with the integrally formed neck 52 and headGl 4). langere 53 and 54, arranged for pulling in opposite directions, as clearly shown in Fig. l0,- and having respectively the knife edges 55 and 56, which bear on opposite sidesof the neck 52 ofthe armature, eliminate entirely, the possibility of any lost motion in the connection of the hangers to the armature. The hangers 53 and 54 are engaged by hooks 5G forining parts of the adjusting bolts 57. The latter projectv through thc diaphragms 27 and 2S, and are' fitted with the threaded nuts 58 for tensioning the diaphragms against each other, as shown in Figs. 2, l0 and 11.

The entire structure as just described, is enclosed bythe casing 62, into whichl` are also fitted the back plate 55, and the ear-piece 64, both of which arev preferably made of some electric insulating material, such as bakelite. The' back plate 68 is provided with' holes'to pass over the threaded ends?J ofthe pins'Y 30, and is secured by the nuts 65. The ear-piece 64 is provided with holes to pass over the threaded ends S1 of the pins 30, andL is secured by the nuts 67. Leads (not shown) and terminals (not shown) in any wellknown forms, may be provided for con# ducting an electric currentto the coil 54.

When a current is flowing through the coil, the armature becomes electro-magnetic, with a certain polarity, and when the current through the coil is reversed, the polarity of the armature is, of course, also reversed.

To describe the action of this instrument in use, wewill sup-pose an electric current to be passing through the coil, in a direction toproduce' the polarity in the armature in# dicate'd by the diagram in Fig. i8, where the south pole of the armature is in the gap between the poles of the permanent magnet.

Such a polarity in the armature, would cause the' S pole of the armature to be attracted by the N pole of the permanent magnet,

and to be rep'elled by the S pole of the per; nia-nent magnet.' Now, if the electric current in the coil is reversed, the polarity of the armature is also reversed, so the end of the a mature in the gap would now become the N pole of the armature. ln this case, the end of the armature in the gap between the poles of the permanent magnet, would befattracted to the S pole thereof, and repelled by the N pole.

By alternate reversals of the electric current flowing through the coil, the polarity of the armature is correspondingly reversed, thereby causing its free end to be pulled Iback and forth while rocking on its knife edge bearing.

rlihe arrows in the diagrams indicate the directions of the magnetic fluxes in the various circuits.

rllhe oscillations of the armature, transmitted through the hangers 53 and 54, in fluente the diaphragms 27 and 28 accordingly. Obviously, any sounds at they sending end of a telephone electric circuit, will produce undulations in the current flowing through the coil 34, and cause vibrations of the armature 40, in exact harmony therewith. These vibrations, being transmitted to the diaphragms, reproduce the sounds which control the sending end of the circuit.

ln the double instrument, as illustrated in Fig. 9, there are two magnets, and 7l; two coils, 'l2 and 73; and two armatures 74 and all these being similar to the corresponding parts in the single instrument.

rihe armatures 74 and 75 have their -free ends superposed as shown in detail inY Fig. l2, the lugs 76 and 77 being slightly offset, and the lug 76 bearing on the conical point portion 78, forming part of the lug 77.

The circular knife edge 79 of the hanger SO, bears on the neck of the lug 7G, while the circular knife edge Sl of the hanger 82, bears on the neck of the lug 77. rlhe combined motions of the armatures 74 and 75 are transmitted to the diaphragms 83 and 84 in the same manner as described for the single instrument.

The diagrams in Figs. l5 and 16 represent the magnetic fluxes and the effects on the armatures, in a Ymanner corresponding to the diagrams in Figs. i3 and 14, of the single instruments.

lt is to be noted that the knife edges of the armatures are in magnetic contact with the permanent magnet, so as not to impede the free passage of the magnetic fluxes.

In emphasizing what has been stated, it will be clear that a. tensionable element, tensioned to be normally under a stress, which may be defined as an initial stress is more susceptible to slight stress increments imposed thereon, than is the same tensionable element susceptible to a stress equal to the increment stress, when this is imposed on the tensionable element in the unst-iessed condition thereof. ln the case of two mutually opposed diaphragins connected to each other as explained, either one may be llt) regarded as the tensionable element for eX- erting the initial stress on the other, in balanced relation thereto.

The stressing of the diaphragms, and ynotably so, the mutual stressing of mutually opposed, identically similar diaphragms, accounts for the remarkable clearness of sound reproduction, possible by the use of this invention.`

It will be observed in the drawing, that the motive power is applied directly, close to the point of use, and that its force is transmitted in very nearly right lines, so thatk therey is practically no loss of power,

as there would be in transmitting motionk through levers, or other power-consuming elements, or from point to point along directional elements forming excessive diagonal components.

The armature, from the center of oscillation to the center of polar application of power, may be made of considerable length, comparatively, so that theangle of oscillation Shall be small, and consequently, the variation ofthe angle between the plane of the armature and the line of action of the connection between the diaphragms, from a right angle, will at all times be negligible. Also, because the connection between the armature and the diaphragm is closely adjacent the poles of the permanent magnet, and remote from the center of oscillation, the bending of the armature in action will be negligible. l

While one diaphragm is under a positive pulling stress from the armature, the inital tension of the other diaphragm remains effective on the armature, allowing it (the said other diaphragm) to follow promptly, the movement of the armature. When the motioii of the armature is reversed, the actions of the diaphragms are also reversed.

The initial tension between the diaphragms should be so adjusted that. the action of each diaphragm in following the motion of the armature, shall hold taut the respective hanger. rIhis establishes a condition where the motions of the diaphragms are substantially simultaneous and identical.

While for convenience, specific embodithe claims in which is embraced a broad generalization of its spirit. n

Having described my invention fully, what I claim is:

l. A sound-emitting element, an oscillating armature arranged to actuatesaid element, aknife-edge bearingl for said armature, and a tensioned spring for holding the armature against the said bearing, said spring comprising a wire acting in the plane of the armature.. i

Q. A sound-emitting element, an oscillating armature having a knife-edge, said armature arranged for imparting motion to said ele:

ment, a bearing for said knife-edge and a tensioned spring for holding said armature against said bearing said spring acting in the plane of the armature.

3. A telephone receiver comprising two diaphragms disposed in opposing relation to each other, a tie joining the diaphragms to each other, an oscillating member having one end thereof connected to the said tie, a knife-edge bearing at the center of oscillation, a spring exerting pressure on said bearing, and means for vibrating the said oscillating member through the influence of an electric current.

4,-. A telephone receiver comprising a permanent magnet, an electro-magnetic armature rhaving a tensionable knife-edge bearing operably mounted between the poles of said permanent magnet, means for energizing said armature, two diaphragms mounted in mutually opposed relation, a tie joining said diaphragms to each other, and means for operably connecting said armature to said tie.

5. An armature having a knife-edge, a permanent magnet having a bearing lfor said knife-edge, a spring arranged to hold the .knife-edge egainst the bearing, a diaphragm connected to said armature, and a coil for actuating the armature. l

6. A permanent magnet having a C-form, an armature arranged to vibrate between the jaws thereof, a bearing for the armature located ropposite the jaws, a spring arranged for tensionably holding the armature against the bearing, a diaphragm connected to the armature, and a coil for actuating said armature.

7. A permanent magnet having a C-form, an armature arranged to vibrate between the jaws thereof, a grooved bearing inside the magnet for said armature, opposite the said jaws; a spring wire tensioned against the outside of the magnet opposite the armature, and a link connecting the spring wire to the armature,

In testimony whereof, I sign my name hereto.

l/VILFRID HEUSSER. 

